---
title: "Input Rollout"
canonical: "https://documentation.chaos.com/space/VMAX/113575441/Input%20Rollout"
format: markdown
---
This page provides information on the Input rollout.
## **Overview**
---
The Input rollout determines the path of the input files for rendering and preview as well as the playback effects. Note that some playback settings require a fractional input frame, in which case the frame is blended between the previous and the next one.
> ℹ️ Field3D files which come from FumeFX must be exported with gzip compression! If they are exported with the default proprietary FumeFX compression, they will not be imported properly in V-Ray Volume Grid.
UI Path
||Select V-Ray Volume Grid|| > **Command panel** > **Modify **tab > **Input **rollout
## **Input**
---
Clicking the “**...**”** **button opens a menu with the following options:
## **Time Bend Controls**
---
This section contains playback options you can use for re-timing a cached sequence. Using these, you can speed up, slow down or animate the motion of the sequence. When re-timing, additional RAM may be used, and loading a new timeline frame may take longer when the frame must be obtained by creating a new one between two adjacent cache files. We refer to the process of creating an intermediate frame from two caches as **Blending**.
---
### **Example: Timeline Origin**
---
### **Example: Cache Origin and Play Speed**
---
### **Example: Looping a Simulation**
---
### **Example: Play Speed**
Large Smoke (Play Speed: 0.1)
---
Gasoline Explosion (Play Speed: 0.1)
---
Burning Fuel (Play Speed: 0.1)
## **Grid Channel Smoothing**
---
> ℹ️ Smoothing is performed after the cache file is loaded for the current frame, so for large grids it could cause significant lag when changing frames. To prevent this from occurring, switch it off during the design process and re-enable it again before rendering.
The controls in this section allow you to smooth the grid channels loaded from cache files for preview and rendering. You can use this to prevent grid artifacts on meshed grid channels such as the Temperature or Smoke, to remove unwanted noise in these channels or to get smooth motion blur by smoothing the Velocity grid channel.
> Macro (anchor)
## **Channels Mapping**
---
> Macro (anchor)
## **Using Environment Variables with Cache Paths**
---
There are path environment variables in every OS, and they can be used with the Volume Grid cache file paths.
For example, to access environment variables in Windows 10 and Windows 8, follow these steps:
1. In Search, search for and then select: **System** (Control Panel).
2. Click the **Advanced system settings** link.
3. Click the **Environment Variables...** button.
4. In the **System variables** section, using **Edit System Variable** (or **New System Variable**) window, specify the value of the PATH environment variable.
Using this, you can create a path (variable), give it a name, and use it for cache files with the Volume Grid.
For example, the path *D:\PhoenixFD\Cache* can be given the environment variable name "*Cache*". In the Volume Grid Input rollout, you can specify the Input Path as the following:
*$env(Cache)\cache_name###.aur*
This loads the cache files in *D:\PhoenixFD\Cache*.
Note that in order to reference environment variables, the following pattern must be used:
***$env(********)***